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1.
Plant Biol (Stuttg) ; 25(4): 571-578, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36920172

RESUMEN

The residues of glyphosate are found to remain in soils longer than previously reported, affecting rhizosphere microbes. This may adversely affect crop and other non-target plants because the plant's resilience and resistance largely rely on plant-associated microbes. Ubiquitous glyphosate residues in soil and how they impact mutualistic microbes inhabiting the aboveground plant parts are largely unexplored. We studied the effects of herbicide residues in soil on Epichloë sp., which are common endophytic symbionts inhabiting aerial parts of cool-season grasses. In this symbiosis, the obligate symbiont subsists entirely on its host plant, and in exchange, it provides alkaloids conferring resistance to herbivores for the host grass that invests little in its own chemical defence. We first show decreased growth of Epichloë endophytes in vitro when directly exposed to two concentrations of glyphosate or glyphosate-based herbicides. Second, we provide evidence for a reduction of Epichloë-derived, insect-toxic loline alkaloids in endophyte-symbiotic meadow fescue (F. pratensis) plants growing in soil with a glyphosate history. Plants were grown for 2 years in an open field site, and natural herbivore infestation was correlated with the glyphosate-mediated reduction of loline alkaloid concentrations. Our findings indicate that herbicides residing in soil not only affect rhizosphere microbiota but also aerial plant endophyte functionality, which emphasizes the destructive effects of glyphosate on plant symbiotic microbes, here with cascading effects on plant-pest insect interactions.


Asunto(s)
Alcaloides , Epichloe , Herbicidas , Herbicidas/farmacología , Suelo , Poaceae , Simbiosis , Endófitos , Plantas , Epichloe/química
2.
Lett Appl Microbiol ; 75(2): 401-409, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35587396

RESUMEN

Dermal replacement materials bioactivated with cyanobacteria have shown promising potential for wound regeneration. To date, extraction of cyanobacteria RNA from seeded scaffolds has not been described. The aim of this study was to develop a method to isolate total RNA from bioactivated scaffolds and to propose a new approach in determining living bacteria based on real-time PCR. Transgenic Synechococcus sp. PCC 7002 (tSyn7002) were seeded in liquid cultures or scaffolds for dermal regeneration in vitro and in vivo for 7 days. RNA was extracted with a 260/280 ratio of ≥2. The small subunit of the 30S ribosome in prokaryotes (16S) and RNAse P protein (rnpA) were validated as reference transcripts for PCR analysis. Gene expression patterns differed in vitro and in vivo. Expression of 16S was significantly upregulated in scaffolds in vitro, as compared to liquid cultures, whilst rnpA expression was comparable. In vivo, both 16S and rnpA showed reduced expression compared to in vitro (16S: in vivo Ct value 13.21 ± 0.32, in vitro 12.44 ± 0.42; rnpA in vivo Ct value 19.87 ± 0.41, in vitro 17.75 ± 1.41). Overall, the results demonstrate rnpA and 16S expression after 7 days of implantation in vitro and in vivo, proving the presence of living bacteria embedded in scaffolds using qPCR.


Asunto(s)
Ribonucleasa P , Synechococcus , Andamios del Tejido , Expresión Génica , ARN , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Ribonucleasa P/genética , Synechococcus/genética
3.
Transl Psychiatry ; 11(1): 544, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34675189

RESUMEN

While a large body of literature documents the impairing effect of anxiety on cognition, performing a demanding task was shown to be effective in reducing anxiety. Here we explored the mechanisms of this anxiolytic effect by examining how a pharmacological challenge designed to improve attentional processes influences the interplay between the neural networks engaged during anxiety and cognition. Using a double-blind between-subject design, we pharmacologically manipulated working memory (WM) using a single oral dose of 20 mg methylphenidate (MPH, cognitive enhancer) or placebo. Fifty healthy adults (25/drug group) performed two runs of a WM N-back task in a 3 T magnetic resonance imaging scanner. This task comprised a low (1-Back) and high (3-Back) WM load, which were performed in two contexts, safety or threat of shocks (induced-anxiety). Analyses revealed that (1) WM accuracy was overall improved by MPH and (2) MPH (vs. placebo) strengthened the engagement of regions within the fronto-parietal control network (FPCN) and reduced the default mode network (DMN) deactivation. These MPH effects predominated in the most difficult context, i.e., threat condition, first run (novelty of the task), and 3-Back task. The facilitation of neural activation can be interpreted as an expansion of cognitive resources, which could foster both the representation and integration of anxiety-provoking stimuli as well as the top-down regulatory processes to protect against the detrimental effect of anxiety. This mechanism might establish an optimal balance between FPCN (cognitive processing) and DMN (emotion regulation) recruitment.


Asunto(s)
Metilfenidato , Adulto , Ansiedad/tratamiento farmacológico , Trastornos de Ansiedad , Cognición , Humanos , Memoria a Corto Plazo
4.
Hand Surg Rehabil ; 40(1): 32-39, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32987168

RESUMEN

Chronic exertional compartment syndrome (CECS) of the upper limbs is less well known than its equivalent in the lower limbs, thus its diagnosis is often delayed. Our goals were to evaluate the impact of CECS on activities of daily living and work-related activities and to report the functional outcomes after minimally invasive fasciotomy. This was a retrospective study of patients with CECS of the upper limb who were operated at two hospitals between 2008 and 2019. Thirty patients were reviewed an average of 5 years after minimally invasive fasciotomy: 26 had CECS of the forearm, 3 of the thenar compartment and 1 of the first interosseous compartment. For the evaluation, patients were asked to assess their pain on a visual analog scale (VAS), complete the QuickDASH questionnaire and rate their satisfaction with the outcome. Preoperative pain on the VAS was 7.45/10 with a negative impact on activities of daily living in 97% of patients, and on work-related activities in 77% of patients with 17% requiring a career change. The mean time to surgical treatment was 5 years. The mean QuickDASH at the final assessment was 6.0 (0-31.8) with a significant decrease in pain on VAS of 1.9/10 (p < 0.01). Seventy-seven percent of patients had very good results while 13% had good results. Full healing was achieved in 63% of patients and physical performance improved in 50%. Seventy-seven percent of patients were either satisfied or very satisfied with the outcome. One patient had a recurrence requiring surgical revision. CECS affects athletes of all levels and impacts both activities of daily living and work-related activities. We need to greatly expand our education and prevention efforts for CECS. Mini-open fasciotomy yields good results.


Asunto(s)
Síndrome Compartimental Crónico de Esfuerzo , Actividades Cotidianas , Descompresión Quirúrgica , Antebrazo , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
5.
Lett Appl Microbiol ; 71(5): 490-497, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32777092

RESUMEN

The aim of this study was to synthesize and investigate the in vitro antifungal properties of 23 cinnamyl Schiff bases. In addition, cytotoxic effects of such cinnamyl Schiff bases against human lung, kidney or red blood cells were also checked. The compounds were synthesized in a single-step, 2 min of reaction under microwave irradiation produced up to 97% yield. Six of the 23 cinnamyl Schiff bases possessed antifungal activities against strains of Candida, Aspergillus, Fonsecaea and, particularly, Cryptococcus species. Indeed, cinnamyl Schiff bases 1 and 23 exhibited minimum inhibitory concentration (MIC) values more than twofold lower than fluconazole (FCZ) against all the Cryptococcus neoformans strains (MIC = 1·33, 1·4 and 5·2 µg ml-1 , respectively) and Cryptococcus gattii strains (MIC = 5·3, 2·8 and 9·2 µg ml-1 , respectively) (12 strains of each species) while cinnamyl Schiff base 11 was as potent as FCZ against all strains from both Cryptococcus species. No significant cytotoxic effects were observed for Schiff bases against human lung, kidney or red blood cells, all presenting selective indexes higher than 10. In conclusion, this study revealed cinnamyl Schiff bases, especially 1 and 23, as new lead anticryptococcal agents for the discovery of novel antifungal drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: The occurrence and severity of fungal infections have increased in recent decades due to resistance to available antifungal drugs and the appearance of new emerging pathogens. Thus, the search for new antifungal agents is mandatory. From a series of 23 cinnamyl Schiff bases, two compounds (1 and 23) were interrogated as new anticryptococcal agents without significant cytotoxicity against human lung, kidney or red blood cells. In turns, these new Schiff bases are lead compounds for the discovery of novel antifungal drugs.


Asunto(s)
Antifúngicos/farmacología , Micosis/tratamiento farmacológico , Bases de Schiff/farmacología , Antifúngicos/síntesis química , Antineoplásicos/farmacología , Aspergillus/efectos de los fármacos , Candida/efectos de los fármacos , Cryptococcus gattii/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Fluconazol/farmacología , Fonsecaea/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Bases de Schiff/síntesis química
6.
ISME J ; 13(5): 1119-1132, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30531893

RESUMEN

Identifying the roles played by individual heterotrophic bacteria in the degradation of high molecular weight (HMW) substrates is critical to understanding the constraints on carbon cycling in the ocean. At five sites in the Atlantic Ocean, we investigated the processing of organic matter by tracking changes in microbial community composition as HMW polysaccharides were enzymatically hydrolysed over time. During this investigation, we discovered that a considerable fraction of heterotrophic bacteria uses a newly-identified 'selfish' mode of substrate processing. We therefore additionally examined the balance of individual substrate utilisation mechanisms at different locations by linking individual microorganisms to distinct substrate utilisation mechanisms. Through FISH and uptake of fluorescently-labelled polysaccharides, 'selfish' organisms were identified as belonging to the Bacteroidetes, Planctomycetes and Gammaproteobacteria. 'Sharing' (extracellular enzyme producing) and 'scavenging' (non-enzyme producing) organisms predominantly belonged to the Alteromonadaceae and SAR11 clades, respectively. The extent to which individual mechanisms prevail depended on the initial population structure of the bacterial community at a given location and time, as well as the growth rate of specific bacteria. Furthermore, the same substrate was processed in different ways by different members of a pelagic microbial community, pointing to significant follow-on effects for carbon cycling.


Asunto(s)
Bacterias/metabolismo , Agua de Mar/microbiología , Alteromonadaceae/enzimología , Alteromonadaceae/metabolismo , Océano Atlántico , Bacterias/aislamiento & purificación , Bacteroidetes/metabolismo , Ciclo del Carbono , Gammaproteobacteria/metabolismo , Procesos Heterotróficos , Polisacáridos/metabolismo
7.
R Soc Open Sci ; 5(10): 181227, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30473858

RESUMEN

Evaluating how populations are connected by migration is important for understanding species resilience because gene flow can facilitate recovery from demographic declines. We therefore investigated the extent to which migration may have contributed to the global recovery of the Antarctic fur seal (Arctocephalus gazella), a circumpolar distributed marine mammal that was brought to the brink of extinction by the sealing industry in the eighteenth and nineteenth centuries. It is widely believed that animals emigrating from South Georgia, where a relict population escaped sealing, contributed to the re-establishment of formerly occupied breeding colonies across the geographical range of the species. To investigate this, we interrogated a genetic polymorphism (S291F) in the melanocortin 1 receptor gene, which is responsible for a cream-coloured phenotype that is relatively abundant at South Georgia and which appears to have recently spread to localities as far afield as Marion Island in the sub-Antarctic Indian Ocean. By sequencing a short region of this gene in 1492 pups from eight breeding colonies, we showed that S291F frequency rapidly declines with increasing geographical distance from South Georgia, consistent with locally restricted gene flow from South Georgia mainly to the South Shetland Islands and Bouvetøya. The S291F allele was not detected farther afield, suggesting that although emigrants from South Georgia may have been locally important, they are unlikely to have played a major role in the recovery of geographically more distant populations.

8.
Syst Appl Microbiol ; 41(4): 408-413, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29747878

RESUMEN

The Thaumarchaeota SAGMCG-1 group and, in particular, members of the genus Nitrosotalea have high occurrence in acidic soils, the rhizosphere, groundwater and oligotrophic lakes, and play a potential role in nitrogen cycling. In this study, the specific oligonucleotide fluorescence in situ hybridization probe SAG357 was designed for this Thaumarchaeota group based on the available 16S rRNA gene sequences in databases, and included the ammonia-oxidizing species Nitrosotalea devanaterra. Cell permeabilization for catalyzed reporter deposition fluorescence in situ detection and the hybridization conditions were optimized on enrichment cultures of the target species N. devanaterra, as well as the non-target ammonia-oxidizing archaeon Nitrosopumilus maritimus. Probe specificity was improved with a competitor oligonucleotide, and fluorescence intensity and cell visualization were enhanced by the design and application of two adjacent helpers. Probe performance was tested in soil samples along a pH gradient, and counting results matched the expected in situ distributions. Probe SAG357 and the CARD-FISH protocol developed in the present study will help to improve the current understanding of the ecology and physiology of N. devanaterra and its relatives in natural environments.


Asunto(s)
Archaea/clasificación , Archaea/genética , Sondas de ADN/genética , ADN de Archaea/genética , ARN Ribosómico 16S/genética , Amoníaco/metabolismo , Hibridación Fluorescente in Situ/métodos , Oxidación-Reducción , Filogenia , Análisis de Secuencia de ADN , Microbiología del Suelo
9.
Free Radic Biol Med ; 106: 368-378, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28232206

RESUMEN

Plasmalogens (Plg) - naturally occurring glycerophospholipids with the vinyl-ether group in the sn-1 position are generally viewed as physiological antioxidants. Although there are numerous examples of antioxidant action of plasmalogen in cell cultures and in experimental animals, this hypothesis is far from being satisfactorily proven due to substantial limitations of such studies. Thus, plasmalogen reactivity in cells results in the accumulation of toxic byproducts and the experimental design is usually too complicated to evaluate the protective function of solely one type of lipid molecular species. In this study, experiments were performed in homogenous and heterogeneous model systems consisting of solutions in organic solvents as well as micelles and liposomes containing pure synthetic plasmenylcholines. Under the experimental conditions used, chemical reactivity of plasmalogens could be attributed to specific fatty acid esterification pattern. This is important because the chemical reactivity cannot be separated from physico-chemical properties of the lipids. Time-dependent formation of phospholipid and cholesterol hydroperoxides were determined by iodometric assay and HPLC-EC. EPR oximetry and Clark electrode were employed to detect the accompanying changes in oxygen concentration. Oxidation of the studied lipids was monitored by standard colorimetric TBARS method as well as MALDI-TOF mass spectrometry. Our data indicate that the reactivity of sn-2 monounsaturated vinyl ether lipids in peroxyl radical-induced or iron-catalyzed peroxidation reactions is comparable with that of their diacyl analogs. In samples containing cholesterol and plasmalogens, oxidative processes lead to accumulation of the radical oxidation product of cholesterol. It can be concluded that the antioxidant action of plasmalogens takes place intramolecularly rather than intermolecularly and depends on the degree of unsaturation of esterified fatty acids. Thus, it is questionable if plasmalogens can really be viewed as "endogenous antioxidant", even though they may exhibit, under special conditions, protective effect.


Asunto(s)
Antioxidantes/metabolismo , Colesterol/metabolismo , Oxígeno/metabolismo , Plasmalógenos/metabolismo , Antioxidantes/síntesis química , Antioxidantes/química , Colesterol/química , Esterificación , Ácidos Grasos/metabolismo , Radicales Libres/química , Radicales Libres/metabolismo , Peroxidación de Lípido , Lípidos/química , Liposomas/química , Liposomas/metabolismo , Micelas , Oxígeno/aislamiento & purificación , Plasmalógenos/síntesis química , Plasmalógenos/química , Solventes/química
10.
Klin Padiatr ; 228(6-07): 313-318, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-27846661

RESUMEN

Background: Chemotherapy-induced peripheral neuropathy is a frequent side-effect of drugs that are used in the treatment of cancer. Affected individuals can suffer from motor, sensory or autonomy nerve damage. Further medication is used for the treatment of CIPN which can cause further side-effects. Patients should be offered physical therapy treatment to relieve the symptoms. Objective: The aim of this article is to give an overview of available literature investigating physical therapy in CIPN in pediatric oncology. Methods: To determine relevant literature, a systematic review was conducted in the databases CINAHL, The Cochrane Library, ERIC, MEDPILOT, PEDro, PsycARTICLES, PsycINFO, PubMed and DIMDI. Besides the methodological quality of the identified literature is supposed to be reviewed. Results: There is no current literature regarding the subject of this article, so no evaluation of the quality could be carried out. Although several publications concerning adults could be identified and transfer could be established for pediatrics. Conclusion: Acupuncture appeared to be effective in the treatment of CIPN in adults. Good results appeared especially regarding pain. Sensorimotor training, balance training, electrotherapy and alternative methods like Reiki and Yoga showed good results for patients symptoms. These treatment methods give a future prospect how CIPN in children can be treated successfully - but further pediatric research is necessary.


Asunto(s)
Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Enfermedades del Sistema Nervioso Periférico/rehabilitación , Modalidades de Fisioterapia , Terapia por Acupuntura , Niño , Humanos , Resultado del Tratamiento
11.
Klin Padiatr ; 228(3): 157-63, 2016 May.
Artículo en Alemán | MEDLINE | ID: mdl-27096304

RESUMEN

Cancer Related Fatigue (CRF) is known as one of the strongest and incriminating side effects of cancer for adults and children. By now there is a lack of valid assessments and sufficient therapy in pediatric oncology. For children it is a tough challenge to accept this overwhelming tiredness and lower activity level in their daily life routines. First positive effects in CFR therapy were found by adults, but this specific scientific field is very young and therefore mostly unexplored. 4 databases for medical and therapeutic journals were systematically searched for RCTs, CCTs and CTs. Systematic reviews were analyzed as well. All studies were carried out in pediatric oncology and deal with exercise therapy. The enclosed studies were valued by PEDro-Scale. Only a handful papers about a potential reduction of CRF in pediatrics could be found, one RCT, 2 CCTs and one CT. No additional results could be found. To summarize the 4 papers, it can be stated that the duration of intervention depends between 2 days and 12 weeks. Also there are differences between the option inpatient and outpatient programs, as well as with or without supervising. The exercise therapy mostly consists of strength and endurance training in combination with warm-up and cool-down programs. This review underlines the importance of developing new assessments. Especially bigger groups of participants should be analyzed with the scope on individualized, supervised program. So far, CRF is underestimated in pediatric oncology and it is very crucial to identify the symptoms. This could lead to an improvement in quality of life.


Asunto(s)
Terapia por Ejercicio , Fatiga/rehabilitación , Neoplasias/complicaciones , Neoplasias/rehabilitación , Niño , Alemania , Humanos , Evaluación de Procesos y Resultados en Atención de Salud
12.
Nature ; 532(7597): 73-6, 2016 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-27078566

RESUMEN

The signature of (60)Fe in deep-sea crusts indicates that one or more supernovae exploded in the solar neighbourhood about 2.2 million years ago. Recent isotopic analysis is consistent with a core-collapse or electron-capture supernova that occurred 60 to 130 parsecs from the Sun. Moreover, peculiarities in the cosmic ray spectrum point to a nearby supernova about two million years ago. The Local Bubble of hot, diffuse plasma, in which the Solar System is embedded, originated from 14 to 20 supernovae within a moving group, whose surviving members are now in the Scorpius-Centaurus stellar association. Here we report calculations of the most probable trajectories and masses of the supernova progenitors, and hence their explosion times and sites. The (60)Fe signal arises from two supernovae at distances between 90 and 100 parsecs. The closest occurred 2.3 million years ago at present-day galactic coordinates l = 327°, b = 11°, and the second-closest exploded about 1.5 million years ago at l = 343°, b = 25°, with masses of 9.2 and 8.8 times the solar mass, respectively. The remaining supernovae, which formed the Local Bubble, contribute to a smaller extent because they happened at larger distances and longer ago ((60)Fe has a half-life of 2.6 million years). There are uncertainties relating to the nucleosynthesis yields and the loss of (60)Fe during transport, but they do not influence the relative distribution of (60)Fe in the crust layers, and therefore our model reproduces the measured relative abundances very well.

13.
Clin Exp Allergy ; 46(3): 479-90, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26609909

RESUMEN

BACKGROUND: Several clinical and experimental studies have implicated IL-33 and its receptor ST2 in the development of asthma. However, the effect of IL-33/ST2 signalling on airway responses and inflammation in allergic asthma is not well established. OBJECTIVE: To investigate the role of IL-33/ST2 signalling in promoting allergen-induced airway hyperresponsiveness (AHR), airway inflammation, antigen-specific IgE production and mast cell activity in a mouse model of asthma. METHODS: ST2-deficient (ST2(-/-)) mice and control BALB/c mice were given house dust mite (HDM) extract over a 6-week period. Forty-eight hours after the final HDM administration, lung function and airway inflammation were evaluated. Airway responsiveness was determined in the central airways and peripheral lung. Cellular infiltration and mast cell protease mMCP-1 levels were quantified in bronchoalveolar lavage fluid (BALF). Recruitment of inflammatory cells and inflammatory cytokine profiles were assessed in pulmonary tissue, and HDM-specific IgE was measured in serum. RESULTS: ST2 deficiency diminished HDM-induced AHR in the peripheral lung, while AHR in the central airways was unaffected. Inflammatory responses to HDM were also reduced in ST2(-/-) mice as reflected by the lower induction of HDM-specific serum IgE, inhibition of HDM-induced eosinophilia and reduced macrophage count in BALF, and a diminished influx of inflammatory cells and reduced goblet cell hyperplasia around the peripheral airways. Furthermore, the levels of the inflammatory cytokines IL-1ß, IL-5, IL-13, IL-33, GM-CSF, thymic stromal lymphopoietin and mast cell protease mMCP-1 were reduced in HDM-treated ST2(-/-) mice compared with wild-type controls. CONCLUSIONS: In addition to promoting Th2 inflammation, we now suggest a role for the IL-33/ST2 pathway for the induction of peripheral inflammation and mucus production that causes AHR in the peripheral lung. This mechanism for inducing AHR at distal parts of the lung may be of specific importance as asthma is considered as a small airway disease.


Asunto(s)
Alérgenos/inmunología , Asma/inmunología , Asma/metabolismo , Proteína 1 Similar al Receptor de Interleucina-1/metabolismo , Pyroglyphidae/inmunología , Remodelación de las Vías Aéreas (Respiratorias) , Animales , Asma/genética , Asma/patología , Líquido del Lavado Bronquioalveolar/inmunología , Quimiocina CCL2/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Inmunización , Inmunoglobulina E/inmunología , Mediadores de Inflamación , Proteína 1 Similar al Receptor de Interleucina-1/genética , Interleucina-33/genética , Interleucina-33/metabolismo , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Mastocitos/inmunología , Mastocitos/metabolismo , Ratones , Ratones Noqueados , Transducción de Señal
14.
J Thromb Haemost ; 13(8): 1503-13, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25988848

RESUMEN

BACKGROUND: Patients undergoing major cardiothoracic surgery are subjected to dilution, owing to massive fluid infusion and blood component transfusion. These patients may experience bleeding perioperatively, and are frequently treated with the endothelium-activating agent desmopressin. OBJECTIVES: To investigate the effect of desmopressin administration on von Willebrand factor (VWF)-dependent coagulant and platelet functions under flow conditions. PATIENTS/METHODS: Blood from 16 patients with postoperative bleeding was obtained before and after desmopressin treatment (0.3 µg kg(-1) body weight), and assessed for coagulant properties and platelet function. Furthermore, VWF antigen levels and multimer composition were determined in both samples. RESULTS: Desmopressin treatment did not change thrombin generation in plasma or whole blood thromboelasticity. Also coagulation factor levels (other than factor VIII) and coagulation times were unchanged, suggesting that desmopressin treatment did not have a major effect on the coagulant activity. On the other hand, desmopressin treatment raised the already high plasma levels of VWF from a median of 116 IU mL(-1) (interquartile range [IQR] 102-154 IU mL(-1) ) to a median of 160 IU mL(-1) (IQR 126-187 IU mL(-1) ) (P = 0.007), owing to accumulation of the high molecular weight VWF multimers. Furthermore, desmopressin treatment caused an increase in collagen-dependent thrombus formation and platelet phosphatidylserine exposure. Markers of thrombus formation correlated with the plasma levels of VWF. In vitro control experiments confirmed a major contribution of VWF to thrombus formation and procoagulant activity under conditions of blood dilution. CONCLUSIONS: Desmopressin treatment of patients with bleeding complications after cardiothoracic surgery induces the release of high molecular weight VWF multimers, which enhance platelet activation and thrombus formation under flow conditions.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Plaquetas/efectos de los fármacos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Desamino Arginina Vasopresina/uso terapéutico , Hemostáticos/uso terapéutico , Hemorragia Posoperatoria/tratamiento farmacológico , Anciano , Pruebas de Coagulación Sanguínea , Plaquetas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilserinas/sangre , Activación Plaquetaria/efectos de los fármacos , Pruebas de Función Plaquetaria , Hemorragia Posoperatoria/sangre , Hemorragia Posoperatoria/etiología , Resultado del Tratamiento , Factor de von Willebrand/metabolismo
15.
Br J Pharmacol ; 172(14): 3650-60, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25847402

RESUMEN

BACKGROUND AND PURPOSE: The cation channel transient receptor potential canonical (TRPC) 6 has been associated with several pathologies including focal segmental glomerulosclerosis, pulmonary hypertension and ischaemia reperfusion-induced lung oedema. We set out to discover novel inhibitors of TRPC6 channels and investigate the therapeutic potential of these agents. EXPERIMENTAL APPROACH: A library of potential TRPC channel inhibitors was designed and synthesized. Activity of the compounds was assessed by measuring intracellular Ca(2+) levels. The lead compound SAR7334 was further characterized by whole-cell patch-clamp techniques. The effects of SAR7334 on acute hypoxic pulmonary vasoconstriction (HPV) and systemic BP were investigated. KEY RESULTS: SAR7334 inhibited TRPC6, TRPC3 and TRPC7-mediated Ca(2+) influx into cells with IC50 s of 9.5, 282 and 226 nM, whereas TRPC4 and TRPC5-mediated Ca(2+) entry was not affected. Patch-clamp experiments confirmed that the compound blocked TRPC6 currents with an IC50 of 7.9 nM. Furthermore, SAR7334 suppressed TRPC6-dependent acute HPV in isolated perfused lungs from mice. Pharmacokinetic studies of SAR7334 demonstrated that the compound was suitable for chronic oral administration. In an initial short-term study, SAR7334 did not change mean arterial pressure in spontaneously hypertensive rats (SHR). CONCLUSIONS AND IMPLICATIONS: Our results confirm the role of TRPC6 channels in hypoxic pulmonary vasoregulation and indicate that these channels are unlikely to play a major role in BP regulation in SHR. SAR7334 is a novel, highly potent and bioavailable inhibitor of TRPC6 channels that opens new opportunities for the investigation of TRPC channel function in vivo.


Asunto(s)
Diglicéridos/farmacología , Descubrimiento de Drogas , Indanos/farmacología , Canales Catiónicos TRPC/antagonistas & inhibidores , Células Cultivadas , Diglicéridos/síntesis química , Diglicéridos/química , Relación Dosis-Respuesta a Droga , Humanos , Indanos/síntesis química , Indanos/química , Datos de Secuencia Molecular , Estructura Molecular , Relación Estructura-Actividad , Canales Catiónicos TRPC/metabolismo
16.
Lab Anim ; 49(4): 284-93, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25650386

RESUMEN

Little is known about the treatment of bone pain in animal models of bone cancer. In the present study, the orthotopic 143-B human osteosarcoma xenotransplantation model was used to address the following questions: (1) Can repetitive analgesic treatment extend the experimental period by prolonging the time to reach humane endpoints and (2) Does repetitive analgesic treatment affect bone tumour development and metastasis? The analgesics, buprenorphine and meloxicam, were either applied individually or in combination at 12 h intervals as soon as the animals began to avoid using the tumour cell injected leg. While control mice treated with NaCl showed continuous body weight loss, the major criterion previously for terminating the experiments, animals treated with analgesic substances did not. The control mice had to be sacrificed 26 days after tumour cell injection, whereas the groups of animals with the different pain treatments were euthanized after an additional eight days. Importantly, primary intratibial tumour growth was not affected in any of the experimental groups by any of the pain treatment procedures. Between days 26 and 34 after tumour cell injection an increase of about 100% of the number of lung metastases was found for the groups treated with buprenorphine alone or together with meloxicam, but not for the group treated with meloxicam alone. In summary, the results indicated that both buprenorphine and meloxicam are suitable analgesics for prolonging the experimental periods in an experimental intratibial osteosarcoma mouse model.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Bienestar del Animal , Antiinflamatorios no Esteroideos/administración & dosificación , Buprenorfina/administración & dosificación , Ratones SCID/fisiología , Manejo del Dolor , Tiazinas/administración & dosificación , Tiazoles/administración & dosificación , Animales , Neoplasias Óseas/patología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Femenino , Inyecciones , Longevidad/efectos de los fármacos , Neoplasias Pulmonares/secundario , Meloxicam , Ratones , Osteosarcoma/patología , Tibia
17.
Free Radic Res ; 49(5): 599-617, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25536419

RESUMEN

Plasmalogens are a unique class of glycerophospholipids (GPLs) containing a fatty alcohol linked by a vinyl-ether moiety at the sn-1 position of the glycerol backbone. There is normally a polyunsaturated fatty acyl residue at the sn-2 position. These two features provide interesting properties to the plasmalogen GPL. Their physiological roles have been challenging to elucidate, although plasmalogens represent up to 20% of the total membrane GPLs in humans. Recent studies have revealed plasmalogen deficiencies associated with several human disorders; therefore, plasmalogens are likely to be specific to different tissues, metabolic processes, and developmental stages. The first chapter of this review will discuss the molecular structure and chemistry of plasmalogens, their biological roles, and their distributions in cells and tissues in different species. In the second chapter, currently used methods of analyzing plasmalogens and their degradation products are described. Although chromatographic methods will be also discussed, special attention will be given to ((31)P) nuclear magnetic resonance spectroscopy and soft ionization mass spectrometry (MS) techniques such as electrospray ionization and matrix-assisted laser desorption and ionization time-of-flight MS. Finally, in the third chapter of this review selected human diseases and disorders, which are presumably characterized by changes in plasmalogen contents and compositions, are described and the analytical methods used are discussed.


Asunto(s)
Técnicas de Química Analítica , Plasmalógenos/análisis , Animales , Cromatografía , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Oxidación-Reducción , Estrés Oxidativo , Plasmalógenos/química , Plasmalógenos/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Relación Estructura-Actividad
18.
Phys Rev Lett ; 113(22): 221101, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25494064

RESUMEN

We report the first direct measurement of the overall characteristics of microwave radio emission from extensive air showers. Using a trigger provided by the KASCADE-Grande air shower array, the signals of the microwave antennas of the Cosmic-Ray Observation via Microwave Emission experiment have been read out and searched for signatures of radio emission by high-energy air showers in the GHz frequency range. Microwave signals have been detected for more than 30 showers with energies above 3×10^{16} eV. The observations presented in this Letter are consistent with a mainly forward-directed and polarized emission process in the GHz frequency range. The measurements show that microwave radiation offers a new means of studying air showers at E≥10^{17} eV.

19.
Ann Surg Oncol ; 20 Suppl 3: S625-35, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23864307

RESUMEN

BACKGROUND: Alpha-fetoprotein (AFP)-secreting hepatocellular carcinomas (HCC) represent a genetically distinct subset of tumors often associated with a worse prognosis. However, the molecular mechanisms that underlie these phenotypic differences remain poorly understood. METHODS: HCC tumor samples from 27 patients were profiled using the Affymetrix 133 Plus 2.0 GeneChips. GeneGO Metacore software was used to identify altered biologic pathways. Expression validation was confirmed by RT-PCR. Manipulation of miR-675 by overexpression and antagomir-mediated knockdown was carried out with subsequent evaluation of effects on cell behavior by cell cycle, proliferation, invasion, and growth in soft agar assays. RESULTS: We identified a strong relationship between primary tumor H19 gene expression and elevated serum AFP. H19 has recently been identified to encode microRNA-675 (miR-675), and we confirmed the relationship in an independent sample of patients. Pathway analyses of the effect of miR-675 overexpression in hepatoma cells revealed a predominant upregulation of cell adhesion and cell cycle initiation pathways. We have demonstrated that miR-675 mediates increases in proliferation and an accumulation of cells with tetraploid DNA content associated with a repression of Rb. We also demonstrated that overexpression of miR-675 alters cellular morphology, reduces invasive potential, and increases anchorage-independent growth capacity. These findings are consistent with a mesenchymal-to-epithelial transition, associated with a reduction in the expression of the key EMT mediator, Twist1. CONCLUSIONS: Expression of the miR-675 in hepatocellular carcinoma links a dramatic upregulation of proliferative and growth capacity with inhibition of motility in HCC cells.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroARNs/genética , Proteínas Nucleares/metabolismo , Proteína de Retinoblastoma/metabolismo , Proteína 1 Relacionada con Twist/metabolismo , alfa-Fetoproteínas/metabolismo , Anciano , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Adhesión Celular , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Perfilación de la Expresión Génica , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Luciferasas/metabolismo , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Células Tumorales Cultivadas
20.
Haemophilia ; 19 Suppl 3: 1-18, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23383607

RESUMEN

The first meeting of international specialists in the field of von Willebrand disease (VWD) was held in the Åland islands in 1998 where Erik von Willebrand had first observed a bleeding disorder in some members of a family from Föglö and a summary of the meeting was published in 1999. The second meeting was held in 2010 and a report of the meeting was published in 2012. Topics covered included progress in understanding of VWD over the last 50 years; multimers; classification of VWD; pharmacokinetics and laboratory assays; genetics; treating the paediatric patient; prophylaxis; geriatrics; gene therapy and treatment guidelines. This third meeting held over 3 days covered the structure and function of von Willebrand factor (VWF); type 1 VWD, the most common form of the disease; a lifespan of pharmacokinetics in VWD; detecting inhibitors in VWD patients; and special challenges in understanding and treating the female VWD patient.


Asunto(s)
Enfermedades de von Willebrand/diagnóstico , Enfermedades de von Willebrand/terapia , Animales , Factor VIII/metabolismo , Femenino , Humanos , Enfermedades de von Willebrand/genética , Enfermedades de von Willebrand/metabolismo , Factor de von Willebrand/metabolismo
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